Two new designs

I've designed two new cages for myself. I first mentioned these in "3D Printing filament" and am reporting on progress. The first cage is based on an evotion bijou and uses the titanium pin they made me. I iterated the fit through about 6 prototypes and now it fits very well.

• In the evotion cage, the glans ring never really held my glans in place. In my cage, it is in the right position and angle for me. Also, I've made it smaller diameter so it does a better job of capturing my glans.
• The pin is in the right position to hold the head of my penis against the end of my cage.
• The head is more enclosed.
• The shaft has length wise slots that allow me to position my penis within the cage.
  
• The cage is tight at the base and the glans but large enough inbetween to keep the loose skin of my penis enclosed.

The image below is printed by Shapeway in versatile plastic.

 

One thing I don't like about the bijou design is that the and the joint have many spaces that regularly get soaked with urine. I've been thinking about alternate ways to secure the pin, but all are somewhat complex and don't eliminate the slots that capture urine.

I also have a Lori tube. I don't wear this often because it is heavy - too heavy for a tube only design. But, it has a PA pin and a security screw. So I started designing another cage.



This is a prototype print. More about the problems home-printing below. I've not been able to try this on yet (due to my penis being locked in another device). I've retained the glans ring - not a feature of the original Lori cage but something I like. I've terminated the tube slats at a ring, largely because that was easier to do.

The real trick was getting the pin position correct. They are hand made so not, um, precise. I rotated the lock block around the shaft so the pin lines up with my off-center piercing. Adjusted the position so the pin end is on cage center line. Then also had to add a rotation of the base to account for the screw hole being not square to the pin curve. The next prototype will tell me.

This cage is harder to put on and off than the bijou style. Better for when M does not choose to play with me, such as trips.

What I like is that the Lori locking screw has fewer and much snugger spaces to collect urine. It does not include the lock, which I need to remain in good working order, lubricated, and un-corroded.

 

As for printing at home, I have a good printer, a Bamboo X1C, but find these devices difficult to print on a fillament deposit printer.

I usually print in a vertical orientation so that the bands around my penis have the greatest strength. There are always some - well, many surfaces that need support. This means printing supports. However, even with supports, the bottom side usually comes out rough. You can see this in the prototype image which was printed head down. All forward surfaces are rough. But, it does mean that the inside of the head was the top and well constructed.

After printing, there are supports to remove. Not all come off cleanly. I can sand some of the rough spots, but that is work. And tricky when the rough spots are difficult to reach.

PLA is the easiest to print and has good dimensional accuracy. It is good for prototypes. However, I don't trust it for a device. It is brittle and prone to snapping. I dread the day that some impact snaps my cage, leaving sharp ends.

I've also printed in PETG, which works well. The last PETG print I did had some irregularities. I may need to dry the material. But it still has the problem of supports and rough edges.

I've printed in straight up nylon 6 (Polytera CoPA). This material is very strong but I could not get a good print. Dimensional accuracy is not as good. it is prone to warping. Supports are very difficult to remove. Adhesion between layers is the weak point. Again, possibly subject to breaking with sharp edges.

I've also printed Bambu nylon impregnated with carbon fibers and it prints much better. Most nylon has CF in it and I think that makes it print easier. But I'm not comfortable with carbon fibers next to my skin. Are they all well bound with the nylon or are fibers shedding off.

So, I had my final version of the first cage printed by shapeway in their versatile plastic. This is a nylon, which I believe is sintered. sintering seems like a much better method for printing devices. I selected their smooth finish. Cost about $100. Dimensional accuracy is very good. It all fits, just like my best prototypes.